1. Field of the Invention
This invention relates to walkers of the type used to aid individuals in walking.
2. Description of the Prior Art
Many different types of walkers are known to those of ordinary skill in the art. One early type of walker comprised a rigid unfoldable frame which allowed an invalid to give himself additional support with his arms while walking. One difficulty with such prior art walkers is that they take up a lot of room and are therefore difficult to transport and store due to their size. An example of a rigid nonfolding walker can be found in U.S. Pat. No. 234,165.
In order to reduce the bulk of prior art walkers, the foldable or collapsable walker was invented. One type of prior art folding walker was invented by Morton I. Thomas and disclosed in U.S. Pat. No. 3, 783,886. Briefly described, that invention comprised a pair of U-shaped support members having feet at one end which are pivotally embraced by a common transversely disposed bar. A special locking means is used to maintain the walker in its unfolded state. A "foldable swingable walker" is disclosed in the patent to Morton I. Thomas and Donald W. Edwards U.S. Pat. No. 3,442,276. Swingable or striding walkers are employed to allow an invalid to advance one or the other of the U-shaped supports in a walking manner. However, striding walkers may be distinguished from other foldable walkers in that the striding walkers are generally not rigidly lockable in a unfolded state. A more recent improvement in the foldable walker art is disclosed in FIGS. 1 - 3 labeled "PRIOR ART". The walker of FIGS. 1 - 3 is discussed in more detail infra.
One major difficulty with prior art foldable or striding walkers is that they are not sufficiently rigid when in the unfolded or operable state. Rigidity is a very important factor since an invalid generally has to be more careful than the average individual and must avoid falling or slipping if at all possible. It has been found that many of the prior art folding or striding walkers had objectionable play in their locking mechanisms which increased the danger to the individual using the walker. One other undesirable feature frequently found in the prior art is that walker legs often have a very limited adjustment range.